My long-term career objective is to become an independently funded, accomplished physician-scientist with clinical and research expertise in the prevention of pyelonephritis and its sequelae in children. As a pediatric nephrologist, I aim t leverage clinical and scientific training to prevent deterioration of kidney function in these patients. To accomplish these objectives, this K08 Mentored Clinical Scientist Development Award proposal outlines a plan to facilitate the acquisition of key research and career advancement skills under the mentorship of Dr. Kirk McHugh. Additional expertise will be provided by Drs. David Hains and Sheryl Justice, two investigators with whom I already have an established record of scientific collaboration and productivity. Together, this Research Advisory Committee will provide guidance to successfully transition from a junior investigator to an independently funded physician-scientist. I will benefit further from state-of-the-art facilities ad core services located at Nationwide Children's Hospital and The Ohio State University. During my training, I will acquire new experimental and analytical skills in the laboratory as well as through classroom- based education at The Ohio State University. I will develop skills in oral and written presentation of research, scientific collaboration, leadership of a research team, and grantsmanship. The long-term research objectives of this work are to elucidate the pathogenic mechanisms of pyelonephritis and its sequelae in children, and to devise improved diagnostic, prognostic and therapeutic approaches to their care. My short-term career goal is to define the pathogenesis of pyelonephritis in children with congenital obstructive nephropathy (CON). Children with CON are especially vulnerable to pyelonephritis, which is an independent risk factor for prolonged hospitalization and progression to end-stage renal disease in this patient population.[1-3] I have identified significant changes in gene expression, morphology, and composition of renal urothelium in a murine model of CON.[4] I hypothesize that CON perturbs structural and functional properties of renal urothelium, placing patients at risk for pyelonephrits and renal scarring. In Specific Aim 1, I will define the relationship between hydronephrosis and structural integrity of renal urothelium. In Specific Aim 2, I will investigate the consequences of CON on bacterial binding and the expression of infection susceptibility genes by renal urothelium. In Specific Aim 3, I will determine if CON increases host susceptibility to experimental pyelonephritis and renal scarring. Completion of these research aims and the training proposed in my educational plan will allow me to develop the foundation to successfully compete for independent R01 funding in the future.